1. Field Of The Invention
The present invention pertains to flexible cellular foam compositions and in particular to flexible polyurethane-based cellular foam compositions and methods for the preparation therefor. More particularly, the present invention relates to the preparation of flexible polyurethane-based cellular foam compositions using catalytically sufficient amounts of an isocyanate trimerization catalyst.
2. Prior Art
The preparation of high resiliency flexible polyurethane-based foam compositions generally entails the reaction of either a polyether or polyester polyol, water, a cross-linking agent, amine catalyst, surfactant and organic polyisocyanate, followed thereafter by the curing of the foam product. In preparing these foams, it is essential that stoichiometric ratios be closely controlled, i.e., that at most only slightly excess amounts over the stoichiometric requirements of organic polyisocyanate be employed. In other words, an isocyanate index of from about 100 to 115 must be employed in preparing these high resiliency flexible foams.
Moreover, in preparing high resiliency flexible foams polymeric isocyanates, as well as additional agents, are required to impart flame retardant properties to the resulting product. Thus, in preparing these foams it is imperative to control the amounts of reactants as well as selectively choosing the ingredients, thereby diminishing the advantages accruing to these foams. It is the alleviation of these problems to which the present invention is directed.